How Obesity and Depression Are Linked

Everyone has experienced a case of the blues, but for many, that can lead to something far more serious. Depression is a very common mental illness, affecting an estimated 1 in 10 adults in America. While the cause of depression has not been fully deciphered, experts are linking obesity to the serious illness as a possible trigger.

What Is Depression?

Major depression is defined by the National Institute of Mental Health as being “characterized by a combination of symptoms that interfere with a person’s ability to work, sleep, study, eat, and enjoy once-pleasurable activities.” It is one of the most common mental health disorders in the United States and can have a debilitating affect on a person’s life.

Obesity & Depression

Just as cases of depression are soaring in the United States, so are cases of obesity. In fact, obesity has now become termed an epidemic in America. But take one look at the statistics and it’s clear why. According to the American Heart Association, more than one-third (34.6%) of adults and 13 million (16.9%) children in the United States are obese.

But what does that have to do with depression? According to many experts, everything. A study published in Pediatrics looked at the correlation between obesity and depression in children. The study focused on 1,000 children ages 9 to 16 over the course of eight years. The findings showed the longer a child is overweight, the greater the risk for depression.

Sarah Mustillo, Ph.D. of Duke University Medical Center notes that depression is most likely rooted in several factors. “The link could have to do with social factors or it could be neuroendocrine-related,” she says. “It could be that if you’re only obese for six months, there’s not as much of an effect as if you were obese for five years…It’s probably a combination of social and biological factors,” she says. “There’s an interaction between what’s outside your body and what’s inside.”

Similarly, a study published in an issue of Clinical Psychology focused on obesity and depression found that the correlation runs both ways—people with obesity are more likely to be depressed and people suffering from depression are more likely to be obese. Individuals who are obese are more likely to become depressed due to a poor self-image, particularly women. Conversely, depressed individuals may be more likely to become obese due to hormone changes and difficulty caring for themselves, such as maintaining an exercise regimen and healthy diet.

While many factors may impact the development of both obesity and depression, scientists are now able to pinpoint the HPA axis hormones as a common biological feature of both. The HPA refers to the highly complex hormonal interaction of the hypothalamus, the pituitary gland, and the adrenal glands. The HPA axis is responsible for keeping hormone balance during stress, and is involved in releasing the “stress hormone” cortisol. As high levels of stress and cortisol have been linked with obesity and depression, this has led researchers to the HPA axis as a key way to better understand both illnesses.

Treatment

Perhaps the most simple and natural treatment for both depression and obesity is exercise. Exercise is not just beneficial to your body; it also impacts your brain. It can cause the brain to release “feel good” endorphins and neurotransmitters, which naturally combat depression. Exercise also reduces immune system chemicals in the body, which can add to depression. What’s more, exercise is a way to boost confidence and improve self-image.

Regardless, depression is a very serious illness and may require additional steps for adequate treatment. A physician may prescribe medication, psychotherapy sessions or both to help treat and manage an individual’s depression. While the use of anti-depressants has been found to be helpful to those with depression, each individual is different and therefore should be open to different treatment options based on individual needs.